Concept explainers
Interpretation:
The Lewis dot structure for the
Concept introduction:
Lewis dot symbols contain dots, which give information about valence electrons.
Lewis structures show bonds as lines and lone pairs as dots.
In Lewis dot
In Lewis dot symbol, valence electrons are represented by dots.
Dots are placed above and below as well as to the left and right of symbol.
Number of dots is important in Lewis dot symbol but not the order in which the dots are placed around the symbol.
In writing symbol pairing is not done until absolutely necessary.
For metals, the number of dots represents the number of electrons that are lost when the atom forms a cation.
For second period nonmetals, the number of unpaired dots is the number of bonds the atom can form.
Atomic ions can also be represented by dot symbols, by simply adding (for anions) and subtracting (for cations) the appropriate number of dots from Lewis dot symbol.
For many molecules, it is impossible to explain all their properties by a single Lewis structure. In such a case, more than one Lewis structure isdrawn to explain the properties. Such structures of a compound are called resonating structures, and this phenomenon is called resonance.
Resonating structure are represented by double headed arrow.
Resonance structure differs only in the position of their electrons, not in the positions of their atoms.
Resonance structures are hypothetical and cannot be isolated.
The rules for drawing the resonance structures are as follows:
Only lone pair of electrons and pi electrons can participate in conjugation in the formation of various resonating structures.
The single bonds present in the molecule do not break or form in the resonance structures.
The placement of atoms present in the molecule remains fixed.
The octet of all atoms is completely filled.
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Chemistry
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- (a) Determine the formal charge of oxygen in the following structure. If the atom is formally neutral, indicate a charge of zero. (b) Draw an alternative Lewis (resonance) structure for the compound given in part (a). Show the unshared pairs and nonzero formal charges in your structure. Don't use radicals. Formal charge on O 0arrow_forwardClassify the following bonds as nonpolar, polar, or ionic: (a) the bond in ClF, (b) the bond in CsBr, and (c) the carbon-carbon double bond in C2H4.arrow_forwardDraw Lewis diagrams for the following ions. In the formula the symbol of the central atom is given first. (Hint:The valence octet may be expanded for the central atom.)(a) BrO4 - (b) PCl6 - (c) XeF6+arrow_forward
- Which statements are true about electronegativity? (a) Electronegativity increases from left to right in a period of the Periodic Table. (b) Electronegativity increases from top to bottom in a column of the Periodic Table . (c) Hydrogen, the element with the lowest atomic number, has the smallest electronegativity. (d) The higher the atomic number of an element, the greater its electronegativity.arrow_forwardCalculate the enthalpy change for the following reactions using the bond enthalpy given below. (Bond enthalpy/kJ : H−H = 436, C−H = 413, C=O = 799, O=O = 495, O−H = 463) (a) H2(g) + 1⁄2O2(g) → H2O(g) (b) CH4(g) + 2O2(g) → CO2(g) + 2H2O(l)arrow_forwardKeeping in mind that some elements violate the octet rule, draw a Lewis structure for each compound: (a) BeH 2; (b) PCl 5.arrow_forward
- Chemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage LearningChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning